polaris 340 for my yerf. HOW?!?!?!?

[gixxerkart]

so i bought a nice polaris 340cc sled motor. going to put it onto my yerfdog 4209. wondering if anyone has done this that's still on here... i pm'd squat, but never got a reply. so my main question is how to run the jack shaft? i need to attach it to the swing arm asm somehow with bearings. im going to utilize the stock drivetrain from the sled, so i'd like to use the secondary clutch with the jackshaft and sprocket on it., and then run that to my axle.
any pics or threads pertaining to this would be awesome. and if somebody would like to take me under their "wing" and teach me about these amazing motors, i'm humble and willing.
thank you! have a great night!

 

[Blazkowiez]

If you want my honest opinion? These karts were made poorly, you'll need to replace nearly everything on the kart. The axles snap with the normal engine which barely runs past 6hp (poor quality. The tie rod ends and ball joints snap (poor quality. The kart is thin metal but looks really cool, that is why they sold so many of them.

I very much believe you want to do this but consider building a kart from scratch with plans.

 

[gixxerkart]

uhh...ya..... im going to need you to not be so negative about my go kart.
my buddy and i have spent the last six months beating the piss out of this thing in order find what's weak, we've replaced everything on this kart, particularly the front suspension and weak welds and the metal piping that was from an old gymnasium.
so, dont rat the kart, tell the tale.
SOOOOOOOOOOOO......
i restate my question, and implore someone to answer w/o dogging on my yerf.

 

[gixxerkart]

if it breaks, build it stronger.
if doesn't exist, create it.
if it ain't fun, sell it.

 

[Kaptain Krunch]

As far as the jackshaft goes, its up to you. Your going to have to be creative. Or maybe im reading your question wrong.

Basically you can mount it with some pillow block bearings, and go from there. If your using the original chaincase from the sled, make brackets for that to bolt to. Make sure you get the center to center distance right between driver and driven, if you don't your CVT will not shift out all the way, or shift out too soon and cause poor acceleration.

I have never used a sled engine in a go kart (went with bike engine, i like to shift), but i am in the process of putting one in a golf cart, and i have been around quite a few sleds, so if you get stuck, feel free to ask.

 

[gixxerkart]

easy parcheesey

 

[gixxerkart]

i like shifting too, but people said the sled motor was easier.... i think i was lied to. lol

 

[gixxerkart]

also, i'm having a really hard time finding what sled this came from. its a polaris 340cc twin f/a head casting says "ec34-q-04" i know its a 340cc motor and the head has 4 ports, but nothing pops up under which motor this came from...
i need that info so i can find the c to c distance...

 

[Kaptain Krunch]

I'm not a Poolaris guy, so i have no clue. However, the people saying a sled engine is easier, that is partially true partially not. With a bike engine you normally don't need a jackshaft, you dont need to gear it down much, and you wont have to re-jet the engine (unless you modify exhaust or intake), however mounting is slightly harder, and you have to make shifter linkage. Sled engines are very easy to mount, and you dont have to make any shifter linkage, but you have to re-jet, and normally you will have to run a dual jack-shaft setup to get enough gear reduction.

As far as center to center distance, you can always grab a belt and eyeball it, as long as the belt isn't too tight i doubt you will notice it. Should be able to get it close enough by eye.

 

[gixxerkart]

wow. that was helpful! so it doesn't matter on the c2c distance as long as the belt remains sloppy around BOTH pulleys? or just the primary pulley? also, why do i need to reduce gearing? is the sled gearing too long?

 

[gixxerkart]

been looking at these pillow block bearings for the jackshaft, but dont know which would be the best option for the price.... i can't blow anything over 20$ on both bearings. but i dont want cheap crap that will seize or break. what do you guys think i should should pick from this site:
http://www.thebigbearingstore.com/

 

[gixxerkart]

krunch-a-tize me capt'n

 

[skeeter]

Try to get the gearing around 10 to 1. Top speed will be around 50 or so. You will have to run a double jackshaft. 10 tooth to a 20 and a 10 tooth to a 50

 

[squat251]

ok, if you plan on going with pillow blocks remember that it is belt driven and that the belt WILL eventually break... point there is make it easy to change the belt. make that mistake and it could be a long walk home. second gem. the c to c wont matter much, just find a belt and assemble accordingly. you should make it adjustable i recommend a post set up with four holes and more drilled at varying distances. you will ideally have a belt that is loose (that is to say, you can wiggle it a little back and forth and side to side not in the secondary of course, well back and forth a little, just not much) if you have a sled to compare it to, check the spacing, thats what you need to aim for. depending on how old the motor is you may not need to re-jet it. just adjust it like you would a brand new mower till it is running smooth in idle, then for accel. this will work well. if you need i can sketch up some of the set ups i have had to hold the secondary. oh, as far as gearing goes, if you can get the sprocket off the main drive barrel (part that moves the track) use that as well as the one on the secondary. if you need to go to a salvage yard and take both the sprocket from the secondary and the one from the barrel off a donor sled (aim for a polaris, with a 340, the exact engine/model isnt too important as the motors should be roughly the same amount of power.) theres a little $.02